Even though we are still early in the growing season and frost is still possible in Scotland in May I am pleased to have harvested my first early potatoes. These were grown in an Air-Pot potato tower which I planted up in February and kept in an unheated greenhouse. Mid May is a good couple of weeks better than last year when we harvested at the very end the month. I know a second planting is possible in these containers but I thought I would try Sweet Potato for a change, this will be a real long shot in Scotland but it would be a great way to use the potato tower; super-early potato followed by Sweet Potato through the warmest months.
I have been getting good results using Air-Pot salad / seed trays. The broad beans germinated really well in an 8 litre tray, with no rotting as often occurs in the cold ground. I found the roots were easy to tease apart when the plants are about 15 cm tall and one tray gave enough plants to fill a 3 metre row with some spares.
An early sowing of radish has produced absolutely perfect little radishes which are being selectively picked to leave remaining plants space to bulk up, but the early thinings are so delicious the rest will not be around for long. A lovely clean crop with no slug damage or holes in the leaves.
The other pot I am using a lot at this time of year is the 1 litre propagation pot. These are currently filling up with assorted peppers, tomatoes, cucumbers and sweetcorn. The sweet potato plants have also been kept in them and are now ready to go into to 50 litre potato tower. Quite a jump; 1 litre to 50 litre, but that is an advantage of Air-Pot containers, there is no need for small increments in pot size, the roots will fill the entire volume of compost.
What is the mix you use for peppers or other plants that like well-drained soil? Last year most of my “dry” herbs (particularly lavender, thyme, and oregano) that I put into air-pot prop cells dried out very quickly, but this year I’ve signs of significant root rot (lavender and sage).
A note on terminology: whatever you recommend, I would prefer to know specific terms, because I don’t know what UK gardening experts mean when they refer to “compost.” In the USA the word refers to the “black gold” end-product of leaves, grass clippings, and other plant matter that has undergone aerobic decomposition (“hot composting”) in a pile over the course of at least a few months. In other words, it is leafmold, but with more than mere leaves as its initial organic matter. Leafmold is therefore one type of compost.
On the other hand, I have heard some UK gardeners call what seems to be potting mix “compost.” That would normally be a difference that I could process, but then I heard experts refer to mixing compost and Innes #3, and while I cannot find definitive, apples-to-apples equivalencies between the Innes numbers and, say, Premier Horticulture’s Pro-Mix types, it does appear to be a potting mix, so referring to a recipe of compost and potting mix would mean nothing more than a combination of potting mix and potting mix. It seems more likely that there’s simply something lost in translation between UK and American gardening jargon.
I ask because last year, after seeing the video “compost and water” video that air-pot posted, I skeptically tried using nothing but leafmold as the container mix in air-pot prop cells, but the results were generally poor; the leafmold dried and baked as a shell within 24 hours. I would be most grateful to know what would be an ideal, well-draining mix for seedlings in prop cells. Thanks in advance for any advice!
Sorry we missed your comment until now, terminology can be confusing when talking about growing medium. Here most chilli / pepper growers favour a general purpose peat based potting mix (what U.K. growers call compost) mixed with something like perlite to improve drainage. I think Air-Pot containers will be free draining enough due to the holes, so tend to favour a mix which retains water & does not shrink unduly if it gets too dry. That is why I suggest a bit of John Innes compost in the mix as this is loam / soil based unlike most mixes on the market in the U.K. which are soil-less, usually peat based. So the suggestion that people mix a bit of John Innes (soil-based) with a general purpose (soil-less compost) is a simple way for U.K. gardeners to get a bit of loam in the mix. You are quite right, it is effectively saying mix a potting mix with a potting mix. Sorry if this is not helpful to overseas growers.
Your experience of small prop pots drying when filled with leafmould is a problem I have had too, the very lightweight pure organic medium does not hold water well, a reason for the loam suggestion. In addition I now stand small Air-Pot containers on a tray & bridge the air space between base & tray with a strip of capillary mat up through holes in base across a bit & down again leaving two tails dangling down. This creates wicks so water can be drawn up into potting mix, most watering will still be from above but now & again some water in the tray ensures compost at the bottom of the pot is wetted. Too much water in the tray is to be avoided or roots grow out of the bottom & are not air-pruned. Be sure to firm the mix into the bottom of the pot to get good contact with the wick. I have recently come across a potting mix made from bracken & sheep’s wool (Dalefoot Compost) which seems very good in Air-Pot. I guess it is a matter of experimenting with what you have available locally, please persevere & I hope you find mixes which work for you.
I appreciate your response! I lost perhaps 6-7 of my lavandula intermedia ‘Phenomenal’ in prop pots, but the good news is that most are recovering well enough, and the two largest ones are thriving in their #3 (9.2L/yellow bases). I had purchased a polyester towel for the specific purpose of cutting it into wicks for sub-irrigated containers, but considering the heat, humidity, and unpredictable rainfall here, using it to run wicks into the prop pots’ bases sounds like a good way to provide much-needed stability.
I think I may have come across more of your content in the chili pepper community in the past. I’m a thehotpepper lurker myself, and that’s actually how I found out about Superoots.
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Yes HipGnosis I must admit to a serious chilli habit. Wicks continue to work well, I am particularly pleased to have them in place as I am away quite a bit this summer & my helpful waterer only has to pour water into the tray. Carefully pouring water into the top of dozens of small containers would probably be too much to expect.